Python: How to sort strings with regards to their trailing numbers?

Question

What is the best way to sort a list of strings with trailing digits

>>> list = ['mba23m23', 'mba23m124', 'mba23m1', 'mba23m5']
>>> list.sort()
>>> print list
['mba23m1', 'mba23m124', 'mba23m23', 'mba23m5']

is there a way to have them sorted as

['mba23m1', 'mba23m5', 'mba23m23', 'mba23m124']

sort(key=lambda s:int(s[6:])) works as long as the prefix is always 6 characters. Otherwise use itertools.groupby or a regex to separate the numbers from the non-numbers. — Samwise
– Samwise, Commented Sep 13, 2022 at 18:09

Shayan Sakha · Accepted Answer · 2022-09-13 18:12:44Z

1

you can use natsort library.

from natsort import natsorted # pip install natsort
list = ['mba23m23', 'mba23m124', 'mba23m1', 'mba23m5']

output:

['mba23m1', 'mba23m5', 'mba23m23', 'mba23m124']

answered Sep 13, 2022 at 18:12

Shayan Sakha

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Comments

YJR · Accepted Answer · 2022-09-14 06:13:36Z

1

Create a function to remove trailing digits and return other part of the string. (Lets consider this function as f_remove_trailing_digits(s) )

you can use following function:

   def f_remove_trailing_digits(s):
           return s.rstrip("0123456789")

Then you can sort using this way

list.sort(key=lambda x:f_remove_trailing_digits(x))

answered Sep 13, 2022 at 19:54

YJR

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Richard Herron · Accepted Answer · 2022-09-13 18:12:15Z

0

Use a lambda (anonymous) function and sort()'s key argument:

ls = ['mba23m23', 'mba23m124', 'mba23m1', 'mba23m5']
ls.sort(key=lambda x: int(x.split('m')[-1]))
print(ls)

Yielding:

['mba23m1', 'mba23m5', 'mba23m23', 'mba23m124']

answered Sep 13, 2022 at 18:12

Richard Herron

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